On a lighter note, Arthur’s personality isn’t entirely insufferably chivalric. She tends not to get the sexual implications of jokes, but can sometimes poke fun at her peers. She had a very close friendship with Lancelot as well as her foster-brother Kay; while she usually seems straight-faced and unwavering, Arthur is very capable of laughing happily and enjoying life with a friend. For someone so kingly she can be surprisingly sassy at times as well, but is usually genuine in her intentions and optimism. There are also a number of things she likes, so it isn’t as though her dedication to kinghood left her devoid of personality, and food is definitely one of Arthur’s favourite things. She has an absolutely voracious appetite and a seemingly infallible metabolism, likely one of the effects of Excalibur’s magic.

In canon Arthur is usually referred to by her fighting class, “saber” (referring to her position as swordsman) to protect her identity, as identities can be used in battles during the Holy Grail War to reveal weapons and other such fallibilities. She is likely to avoid using her real name at first in Ruby City (and will likely use earlier translations of the name) as she won’t know the status of the Grail War and does not expect most to know all translations of the name of the legend.

In the beginning of her stay in Ruby City Arthur will be dealing with the final events of the Fourth Grail War. It is revealed to Arthur that the insane of the servants, Berserker, is actually Lancelot, her dearest friend. After she defeats him he explains that he went mad because though Arthur knew of his affair with Gwenivere, she never raised a hand to punish him:

"Because I could not stop myself from loving Gwenivere, I was unable to forgive myself. But King Arthur, you never so much as questioned me or sought recompense. You simply stood before us in your righteousness. But I wished for judgement at your hand. Had your anger punished me, I might not have fallen into madness in my quest for atonement."

He continues on to tell her that though this occurred, he could say with certainty that Arthur was the greatest of kings. This statement does not stay with her; she still feels the need to fight for the grail and fix the mistakes she has made. When her master orders her to destroy the grail, she is unable to do so, instead perishing before the grail is destroyed. As she delivers the attack of her Noble Phantasm, she states

"What could [my master] have learned about me from issuing a mere three orders? After all, I never even knew my closest companions. Perhaps this is my punishment for being the king who could not understand the feelings of others."